摘要:
Dans la branche supérieure du dispositif, une horloge (9) fournit un signal carré à haute fréquence qui, après avoir été divisé en (10) et (11) et réglé en amplitude par (12) et (13), est introduit dans le filtre (14) pour être converti en signal sinusoïdal de référence et comparé dans le comparateur (8) au signal de découpage fourni par le générateur d'ondes triangulaires (7). Dans la branche inférieure, un générateur (15) émet un signal fondamental qui est synchronisé avec le signal d'horloge en (16) et additionné l'un à l'autre en (17) pour obtenir un train d'ondes divisé en (18) et (19) et réparti en trois signaux d'échantillonnage déphasés de 120° introduits en T dans les bistables à commande par flancs (20, 21 et 22). Après comparaison de l'onde sinusoidale et de l'onde triangulaire de découpage dans le comparateur (8), on obtient un signal haché complexe qui, traité en (20, 21 et 22) donne des ondes modulées en largeur.
摘要:
Circuits and methods for switched mode operational amplifiers are provided. In some embodiments, circuits are provided, the circuits comprising: an amplifier having an output; a first pulse width modulator (PWM) having an input coupled to the output of the amplifier and using a first periodic reference signal waveform; and a second PWM having an input coupled to the output of the amplifier and using a second periodic reference signal waveform, wherein the second periodic reference signal waveform is 180 degrees out of phase from the first periodic reference signal waveform. In some embodiments, circuits are provided, the circuits comprising: an amplifier having an output; and a plurality of pulse width modulators (PWMs) each having an input coupled to the output of the amplifier and using a corresponding unique one of a plurality of periodic reference signal waveforms, wherein the plurality of periodic reference signal waveforms are shifted in phase.
摘要:
Technologies for communicating information from an inverter configured for the conversion of direct current (DC) power generated from an alternative source to alternating current (AC) power are disclosed. The technologies include determining information to be transmitted from the inverter over a power line cable connected to the inverter and controlling the operation of an output converter of the inverter as a function of the information to be transmitted to cause the output converter to generate an output waveform having the information modulated thereon.
摘要:
A positioning driver ( 32 ) for a voice coil motor ( 22 ) in a disk drive system ( 10 ) is disclosed. Pulse-width-modulated prestage drivers ( 46 ) are coupled to power transistors ( 50 ) arranged in an "H" bridge for driving the voice coil motor ( 22 ), biased with a power supply voltage (V M ). The pulse-width-modulated prestage drivers ( 46 ) drive the power transistors ( 50 ) according to a comparison between an error signal from an error amplifier ( 36 ) and a ramp clock signal (RMP) generated by a ramp clock generator ( 46 ). The ramp clock generator ( 46 ) includes a control circuit ( 68 ) that modulates the high and low limits of the ramp clock signal (RMP) in response to variations in the power supply voltage (V M ). This modulation of the high and low limits compensates for variations in the gain of the power transistors ( 50 ) resulting from variations in the power supply voltage (V M ). The control circuit ( 68 ) may also modulate the slope of the ramp clock signal (RMP) according to variations in the power supply voltage (V M ), for example to maintain a constant frequency.
摘要:
Die Erfindung ist ein Verfahren zum Betrieb einer Antriebssteuerungseinrichtung (68), die einen Umrichter (10) mit einem Spannungszwischenkreis umfasst, und eine nach dem Verfahren arbeitende Vorrichtung, wobei im Betrieb mittels des Umrichters (10) erzeugte Phasenströme gemessen werden, wobei aus den gemessenen Phasenströmen ein Stromvektor ( i αβ ) in einem ersten Koordinatensystem (αβ-Koordinatensystem) gebildet wird, wobei der Stromvektor ( i αβ ) um einen Transformationswinkel (ϕ fSH ) in ein zweites Koordinatensystem (xy-Koordina-tensystem) gedreht wird, wobei ein resultierenden Stromvektor ( i xy ) in dem zweiten Koordinatensystem einem Regler (36) zugeführt wird, wobei ein am Ausgang des Reglers (36) resultierender Spannungsvektor (d u xy ) um denselben Transformationswinkel (ϕ fSH ) zurück in das erste Koordinatensystem gedreht wird und wobei der resultierende Spannungsvektor (d u αβ ) in dem ersten Koordinatensystem als zusätzliche Einflussgröße zu Ansteuerung des Umrichters (10) verwendet wird.
摘要:
The invention, which relates to a method for regulating a centre voltage, is based on the object of specifying a method which implements simplified centre regulation, allows a reduction in the outlay of hardware and software components and hence can be used inexpensively. This object is achieved by measuring the intermediate circuit capacitor voltages and ascertaining the centre voltage from these measured voltages, and taking the position of the centre voltage as a basis for shifting the timing of the switch-on and/or switch-off edges of the switching voltage, the absolute value and direction of the shift being dependent on the position of the centre voltage.